I've done every 5 man heroic many times as 5 paladins (holy, prot, 3 ret). Most of them are doable with a prot and 4 ret after you're geared.

I find oculus very easy and I don't have any special macros. My winning strategy for ley-guardian is:
1. use all Ruby drakes
2. Put healer on the ground and make him not follow. No drake, just heal.
3. turn on FTL DPS Keys -- standard for any vehicle fight.
Then during the fight it's just a matter of spamming the attack button, which will also take out the little drakes when they come, hitting evasion every time it's up, and using the taunt button (martyrdom i guess?) on the one guy I want my healer to primarily focus on (i click it so it doesnt broadcast). Fly around during phase shift and that's about it.

The only 5 man content I really have a problem with as 5 paladins is the abominations in the lich king escape. Without nature resist, I have to be very careful that 1 or fewer aboms is facing my team at any given time. My holy paladin tends to die if they both spray him, and then it's really annoying to start the event over. I'm levelling up some other teams though, and may end up swapping a shaman into my paladin team for nature resist and other goodies